Objective The research for auditory steady state response (ASSR) is important for understanding the auditory system in human brain.Unfortunately, the devices for generating the auditory stimuli in previous research are expensive yet inconvenient.This paper proposes a novel portable auditory stimuli generator for ASSR experiments.Methods The main processor of this system is TI’s TMS320C5515 digital signal processor (DSP).A SD card is used to store configuration files and sound files which specify the sound stimuli.The main processor reads data from the SD card through the SD interface and the DMA channel.Then, the data are transmitted from the processor to an audio coder and decoder (CODEC) through the I2S bus and finally achieves the sound playing.A graphic user interface is provided for the user to choose the configuration file.Moreover, a toolbox based on MATLAB is offered to translate the common music formats into the compatible sound format.Results The permissible sampling rates for playback range from 8kHz to 192kHz.The channels can be either mono or stereo, and the data resolution can be 16bits or 32bits.The playback volume can be adjusted in 87.5dB’s range, and the step for adjustment is 0.5dB.A series of ASSR experiments have been conducted on 4 subjects to demonstrate the feasibility of this system.Conclusions This system can be used successfully in the ASSR experiments to provide long-term and stable sound outputs.The system holds a power-consumption less than 200mW.With a 1000mA·h and 3.7V’s lithium battery, this system can keep on working for more than 18.5h.